Seat-hinge.



No. 708,|63. Patented Sept. 2, I902.

. L D PETRE SEAT HINGE. (Application filed. m 22, i901.

2 ShgtsF-Sheet I.

( No Model.)

The man PETERS 00.. PHOTO-LITH m5. 708,!63. Patented Sept. 2, I902. L.D. PETRE.

: SEAT HINGE.

(Application filed May 22, 1901.) (No Model) 2 Sheets-Sheat 2.

THE Mona l tnms 90v. mum-um wAwlmronl D. C

UNiTED STATES PATENT OFFICE.

LEWIS D. PETRE, OF CHICAGO, ILLINOIS.

SEAT-HINGE.

SPECIFICATION forming part of Letters Patent NO. 708,163, dated.September 2, 1902.

' Application filed May 22,1901}.

To all whom it may concern..- 7

Be it known that I, LEWIS D. PETBE, a citizen of the United States,residing in Chicago,

in the county of Cook and State of Illinois, have invented new anduseful Improvements in Seat-Hinges, of which the following, when takenin connection with the drawings and ref erence characters thereon andforming a part hereof, is a full and complete description.

The invention relates to seat-hinges for opera-chairs, school-desks, andother articles of furniture having a hinged seat.

The object of my invention is to obtain simply-constructed hinge wherebythe seat may be easily and noiselessly raised and lowered and to producea hinge without the necessity of a bolt in its construction, therebyreducing to a minimum all liability of its becoming inoperative, and atthe same time to produce a hinge the principal parts of which may bemolded as parts of the standard and seat-arm of an opera-chair, therebygreatly reducing the cost of its manufacture.

Figure 1 of the drawings hereby made part of this specification is aside elevation of the seat-hinge embodying the invention with a portionof the immovable part removed to ex-. pose to View a movable abutmentand spring placed therein. The ball-tracks, groove, and obscure partsare shown by dotted lines. Fig. 2 is a side elevation of hinge embodyingthe invention with seat-arm lowered to position when seat is in use,showing the relative position of the different parts of hinge, also.showing the position of the ball in regard to the tracks. A portion ofthe projection of seat-arm is broken away to show a stud upon which themovable part rests. Fig. 3 is avertical sectional view on line 3 3viewed in the direction indicated by the arrows in Fig. 1. Fig. 4 showsthe lenticular track placed in the circumferential face of a projectionof seat-arm, a portion of the seat arm being broken away. Fig. 5'showsthe lenticularshaped track in the movable abutment of seat-hinge.

Throughout the specification like parts are indicated by likecharacters. 4

A, Figs. 1 and 2, is the immovable part of hinge, having a centralopening B, into which stud a projects, also having a recess opposite ofhinge may be fastened to a standard.

Serial No. 61,440. (No model.)

to such stud, in which movable abutment C is placed.

D is a seat-arm of an opera-chair, to which a seat may be attached. Saidseat-arm D is provided with a projection d, which rests upon stud a, asshown in Figs. 1 and 2.

E is a groove placed in the circumferential face of projection 01, asshown by dotted line 0 o in Fig. 1 and atE in cross-sectional view, Fig.3, so that when seat-arm D is in position indicated in Fig. 1 saidgroove E is concentric throughout the greater part to the concave topsurface of stud a.

F is a track in the opposite circumferential face of the projection 61.Such track is lenticular in form, the sides thereof converging at eitherend at an acute angle.

0 is a movable abutment placed in a recess in the immovable part ofhinge, as clearly shown in Figs. 1 and 2, said abutment having a track Htherein, which is lenticular, the sides thereof converging at either endat an acute angle and so placed that when seat-arm is in positionindicated in Fig. 1 such track will be opposite to and facing track F.

I is a ball interposed between projection 03 of seat-arm D and movableabutment Q within tracks F and H in each respectively.

K is a spring placed in recess in immovable part of hinge between themovable abutment O and side a of immovable part A, yieldingly holdingthe hinge in a working position.

L L are means whereby the immovable part If desired, the immovable partof hinge can be molded as part of a seat-standard, thereby doing awaywith the necessity of suchmeans to attach said immovable part to aseat-standard.

The projection (Z of seat-arm D is placed within the central opening Bof immovable part A, so that it will rest and turn upon the the ball Itravels from the position indicated in Fig. 1 in a constantly-narrowingtrack, which forces the ball upward. When the seatarm D is lowered,projection dis turned upon stud a. Track F in said projection is alsoturned, while track H in movable abutment 0 remains stationary, exceptas said track II is forced upward in the upward movement of abutment Oby reason of ball I traveling in a constantly-narrowing track until theball is pinched between ends f and h of said tracks F and H,respectively, as clearly shown in Fig. 2. Movable abutment C is therebyforced upward, partially overcoming the tension of spring K, until saidabutment is forced up against the side a of immovable part A. Theforward motion of seatarm D is thereby stopped, and the seat is held inits proper position for use as a seat. I find that if a spring K is usedhaving a weak tension movable abutment C will force said spring againstthe top edge a of immovable part A; but this is due to the difference inthe tensions ofsprings.

I prefer to have the grooveE of such shape that a cross-sectional viewthereof will show a V-shaped track, as indicated in Fig. 3, and the topsurface of stud a convex in crosssectionalview, as also shown in Fig.3,so that the lines of contact between said seat-arm D and stud a are arcsof circles within groove E and upon stud a, respectively. By this meansI reduce the friction of the hinge to a minimum. This will be clearlyseen by referring to Fig. 3. I also prefer to have the concave top 4 4of said stud a of as short an are as possible, but of sufficient lengthto prevent the seat-arm Dfrom becoming an eccentric upon its reachingits extreme limit when the seat is either raised or lowered. I alsoprefer to have the tracks F and H V-shaped in cross-sectional view, asshown in Fig. 3.

Movable abutment O, in connection with spring K, has for its primaryobject the production of a means whereby the seat-arm D is checked inits turning motion and also to bring it to a full stop. They alsoprovide a means whereby the different parts of the hinge are kept in aconstantly-working position, and any slight inaccuracies in the moldingof the respective parts become immaterial, owing to the tension ofspring K. They also provide a means whereby the seat can be assembled.

In assembling the hinge projection d is placed within the centralopening B of immovable part A, resting upon stud a within groove E. BallI may then be placed in track F, after which movable abutment C may beplaced in the recess of central opening B, resting upon ball I, whichball will thus be interposed between tracks Fand H. Spring K may then beinserted.

I claim- 1. In a seat-hinge, an immovable partA having a central openingB and provided with a stud a; a seat-arm provided with a projection dhaving groove E and track F in its circumferential face, such projectionof seatarm resting upon stud a of immovable part A within groove E;movable abutment O having a track H therein; aspringK interposed betweenmovable abutment O and side a of immovable part A; a ball I interposedbetween movable abutment O and projection (1 within tracks H and F ineach respectively, substantially as specified.

2. The combination of aseat-arm provided with a projection having trackand groove therein, an immovable part having a central opening and arecess therein and also provided with a stud extending into said centralopening and upon which stud the projection of seat-arm rests and turnswithin said groove in the circumferential face of the projection ofseat-arm, a movable abutment having a V-shaped track therein for a ballplaced in said recess in immovable part, a ball interposed between thecircumferential face of projection of seat-arm and movable abutment intracks in each respectively, a spring yieldingly holding movableabutment in working position, substantially as specified.

3. The combination of a seat-arm having a projection with a groove andtrack in the circumferential face of such projection, an immovable partprovided with a central opening and a recess and a stud having a concavetop surface upon which the projection of seatarm rests and turns, amovable abutment set in said recesses in the opening of said im movablepart and provided with a track therein for a ball, a ball interposedbetween the projection of seat arm and the movable abutment in saidtracks in each respectively, and a spring yieldingly holding movableabutment in a working position and confined in its limit of operation byimmovable part, substantially as specified.

4. An immovable part having a central opening and a recess and providedwith a stud having a concave top surface; a seat-arm provided with aprojection having a groove in its circumferential face and also having aV- shaped track, such track being lenticular in form, the sides thereofconverging at either end at an acute angle, and placed on the oppositecircumferential face of such projection to said groove; a movableabutment placed in said recess in immovable part and provided with alenticular V-shaped track the sides of which track converge at eitherend at an acute angle; a ball interposed between the projection ofseat-arm and the movable abutment within said tracks in thecircumferential face of such projection and movable abutmentrespectively, and a spring yieldingly holding the movable abutment in aworking position, substantially as specified.

5. An immovable part molded as part of a seat-standard, having a centralopening and a recess, also a stud having a. concave top; a seat-armprovided with a projection, such projection having a groove within whichthe stud of the immovable part is placed, and

angle; a movable abutment placed in said recess in immovable part ofhinge, said abutment having a track therein which track is lenticular inform, the sides thereof converging at either end at an acute angle, saidabut ment being so placed in immovable part that the track therein shallbe opposite to and facing the track in the projection of seatarm; aspring yioldingly holding abutment in working position, and a ballinterposed between movable abutment and the circumferential face ofprojection of seat-arm, substan- 2o tiall y as specified.

LEWIS D. PETRE.

In presence of WILL H. CLARK, HIRAM I. KECK.

